Dioxide
/daɪˈɒksaɪd/noun
A compound containing two oxygen atoms or one molecule of oxygen combined with another element.
Did you know?The first element, di-, comes from Greek for “two,” while oxide comes from the same ancient root behind “acid” and “oxygen,” so the word is basically a numbered oxygen-formula in disguise.
Etymological Timeline
Ancient Greek
Greek
dis
“two”
18th Century
French
oxide
“a compound of oxygen with another element”
Late 18th Century
English
oxide
“a compound containing oxygen”
19th Century
English
dioxide
“an oxide containing two atoms of oxygen or two oxygen equivalents”
Modern English
English
dioxide
“a compound with two oxygen atoms or two oxygen equivalents”